Clear your doubts guys!!!
Ok, so here's the deal, in a very longwinded way that should hopefully explain everything and answer ALL questions.
You have an SD card in your phone and, a bit like normal PC Hard Drives, you can "partition" them (split them into two or more sections of different filesystems). Normally, your SD card is just one big FAT32 partition, which is fine for storing your pics, messages, emails, etc.
Now, other then your Phone's SD card, your phone will have its own internal flash memory (or "NAND") storage. Tradditionally with Android, you could only install applications to this NAND storage, you cannot install them onto your SD card. So if you have an empty 32GB SD card, but only 5Mb of internal phone storage, you still wont be able to install many apps, if any at all.
This was done to protect the apps from things like piracy - it's not easy to access the location where apps are installed on your phone's internal storage (normally impossible without root), so you can't for example buy an app, copy it, refund it, then install it again.
Still, this is no good for those of us who like to install lots and lots of apps, legitimately, as we run out of internal storage very quickly.
So Google came up with a way to install apps to the SD card. A folder is created called something like .android_secure and this stores (I believe) encrypted versions of applications, but there's a few catches:
1) Apps aren't automatically stored here, you have to manually "move" them
2) Not all apps are capable of being moved, in fact most apps aren't, the developer needs to update their app and allow it. Some apps aren't and wont be updated and some developers may not want to allow it for whatever reason.
3) Not all app data is moved, most of it is but some data is left on your phone so many people still run out of internal storage quickly.
4) You can force ALL apps to be moved to this area by default, but it breaks incompatible ones - such as Widgets, which are unable to load due to the SD card not being "prepared".
So that's Froyo's version. Before Froyo existed, some very clever people came up with a thing called "Apps2SD". Remember I said that your SD card normally is one big FAT32 partition? Well, Apps2SD works by having your SD card patitioned into TWO filesystems. A normal FAT32 partition for your usual stuff and a secondary "EXT" partition. EXT is just a filesystem, like FAT32 or NTFS, but it's the filesystem used by Android internally. The SD card is normally FAT32 because it's a "universal" filesystem, that just about any machine will be able to read, whereas EXT filesystems are generally Linux only, but I digress.
EXT has several different versions. The most common one you'll see is ext3. The main difference between ext2 and ext3 is "journaling", which is just a fancy way of saying that should an operation (such as copying, writing or reading) be interrupted unexpectedly (say, by you turning your phone off), then no data should be lost or corrupted. You know how when you turn your phone on, it says "preparing SD card"? It takes a few minutes, but what it's actually doing is checking that the FAT32 partition hasn't been damaged, because FAT does NOT have journaling. If you used a computer back in the Windows 98 days, you may remember that lovely blue "Scandisk" screen that had to run every time you didn't shut your computer down correctly - that's the same thing. But then Windows 2000/XP came along with NTFS, which also has journaling, meaning you had less chance of loosing data. But I digress once more.
So you have your SD card partitioned into EXT and FAT32. Generally it doesn't matter if it's ext3 or ext4, but you don't get any real advantage with ext4 over ext3 in this instance. Apps2SD then runs a special script on your phone which "symbolically links" the folder from your phone's internal storage where your apps are normally stored, to the ext partition on your SD card. A symbolic link is a bit like a shortcut for folders, except it's transparent to the OS: In other words, Android doesn't know that when it's installing it's apps to the internal phone storage, it's actually being stored on the SD card. This effectively boosts your internal phone memory from the previous 5mb that you had in my example above, up to whatever size you made the ext partition on your SD card (often 512Mb or 1Gb, but it depends on how many apps you install).
Plus, because it's "journaled", it doesn't need to be "prepared", meaning it's ready to go as soon as the phone starts - so your widgets and apps work immediately (unlike "forced" Froyo Apps2SD, where widgets disappear).
The catch with Apps2SD is that whatever space the ext partition takes up is taken away from the SD card. So if you have a 4Gb card (with something like 3.5Gb of actual storage) and you make a 512Mb ext partition, your SD card will "shrink" to 3Gb. The space isn't actually lost, it's just being used by the ext partition. If you reformat your card, you'll get it back.
Finally, there's a difference between "Apps2SD" and "Apps2SD+". Remember I said that your apps are stored on a special folder inside your Phone's NAND storage? Well, that was a bit of a lie. It's actually stored in TWO places. There's a second area which is called the Davlik Cache. You don't really need to worry about what this is for (Hint: IT's to do with the Java runetime your phone uses to run apps), all you need to know is that apps use it to store data, which also eats up internal phone memory. Apps2SD+ moves davlik cache to the ext partition on your SD card as well, freeing up even more space. Some people believe that this may come at the cost of performance, as the internal NAND memory should be faster than your SD card (Which is why you also get people arguing over which "class" SD card is better for Apps2SD - the logic being that a faster SD card means less impact from this move), but the truth of the matter is that your applications will be running from your Phone's RAM anyway, so performance isn't really impacted at all. Since most apps are only a few hundred Kb's in size, or a couple of MB at the most, it's a non-issue.
Finally, any recent version of Apps2SD/Apps2SD+ should work with an SD card that is or isn't formatted with an ext partition. It'll check for this partition when your phone first boots and if it's not there, just use internal phone storage.
Having an ext partition WITHOUT Apps2SD+ shouldn't cause any issues, either, so you can format your SD card whenever you're ready.
So in summary:
Apps2SD "fakes" your phone's internal memory and puts it all on a hidden section of your SD card.
Apps2SD+ pushes even more content to the SD card, freeing up even more space on the phone itself.
"Froyo" Apps2SD has various limitations that "old" apps2SD does not, but is much easier to handle as it doesn't involve any kind of "partitioning".
Related
Hey there,
the U8800 has a 2GB partition which isn't used at all when an external SD-card is installed.
The internal 2GB partition is mounted to /HWUserData and is accessible. Now I want to use it for my apps. With the typical App2SD-apps that are available in the market I cannot move the apps to this partition. They are always moved to the external card.
Moving the apps manually is not very helpful as Android treats them as install-packages when I open them within the file manager.
tl;dr: The 2GB-partition does only show up within the file manager, how can i use it for apps etc.?
XphX
http://forum.xda-developers.com/showthread.php?t=1112857
Thank your for your answer; I do not want to use that program; I fear voiding the warranty. I have no problem with installing custom-ROMs, but I won't change the partitions of the internal memory.
I'll take out the external SD-card for a moment, maybe I can install the apps to the 2GB-part then...
Seriously, why does Huawei include 2GB of memory if it is not usable?
Use the default apps2sd option.
I've been thinking about this myself and thought about changing the mount points so the internal 2GB SD is formatted as ext then linked to /sd-ext and used as an a2sd partition. The advantage is that, unlike normal a2sd, you will still be able to remove the microSD card.
The problem would be that recovery images wouldn't like this as they always expect a2sd to be the second partition on the microSD. It would also stop the backups from working..
It's something I'll need to think about a lot.
flibblesan said:
The advantage is that, unlike normal a2sd, you will still be able to remove the microSD card
Click to expand...
Click to collapse
That is exactly what I want to do. a2sd simply does not recognize the partition as it expects it to be a second partition within the external sd. Could changing the mount point resolve this issue? Where would I even mount it to? The external card will still be the one recognized (or not?)..
My main problem is I have LOTS OF APPS. Because of this, I have to move them to the microSD card. The apps I usually move are the ones that eats up lots of space like games.
I've noticed another problem when I started moving the games unto my microSD card. Since the games has music files as well (like sound effects and in-game songs and whatnot) whenever I open a media player such as Ubermusic for example, I've noticed that those game music files also gets detected by Ubermusic. Because of this, whenever I choose "Shuffle All" and play all my music there would be times that I would hear Angry Birds squawking and them evil pigs getting smashed mixed in with my songs. (^_^") It has grown into a huge problem for me, since I can't move them back to the /data partition as there isn't any space left in there.
Currently, I use App2SD Pro to move those apps, and I hate it because even if you choose "Move All Apps" you still have to manually move them by pressing the button one by one and it has been so time-consuming. Because of this, I've been on a search for a proper solution.
Please correct me if I'm wrong.
Based on my personal research, I believe that we can partition the microSD card in such a way that it can have a /data partition of it's own, and that's what we call SD EXT right?
If that's true, does that mean that if I have this set up in my microSD card and my /data partition is full of apps, will the next app that I would install automatically gets installed to the SD EXT? Or do I need an app like Link2SD (based on my own research, I believe this app requires an SD EXT to work properly.) to manually transfer the apps that would not fit in the original /data partition?
And can someone please confirm-- since the app "Link2SD" says "link", does this mean that it just "links" or creates a "shortcut" in the microSD for the apps or does it really move the apps in the microSD?
And last but not the least, can someone point me out to the right direction where I can find an easy to follow guide (if there's any) to be able to create an SD EXT partition in my microSD card.
Oh, and by the way, I have a 16GB Samsung SDHC Class 2 microSD card if that would help.
Thanks in advance for all those that would help out! This community has never failed me, and I'm proud to be a part of it!
les02jen17 said:
Based on my personal research, I believe that we can partition the microSD card in such a way that it can have a /data partition of it's own, and that's what we call SD EXT right?
Click to expand...
Click to collapse
I may be new in posting, but as far as I know: SD-EXT is the whole sd card itself when your device does support internal second usb storage (also named sd card). That is the case for my Galaxy S2 where SD-EXT only refers to my EXTernal (i.e. removable) sd card; there's a fixed (internal) sd card too.
SD-EXT does not mean anything else for me.
Hope that'd be useful.
les02jen17 said:
And last but not the least, can someone point me out to the right direction where I can find an easy to follow guide (if there's any) to be able to create an SD EXT partition in my microSD card.
Oh, and by the way, I have a 16GB Samsung SDHC Class 2 microSD card if that would help.
Click to expand...
Click to collapse
I'm guessing you are on a custom ROM. You can partition your SD with CWM recovery. If your ROM supports apps2sd it will use the ext partition.
Class 2 is letter used for storage than performance, though.
Sent from my NookColor using xda premium
Hello Guys
I would like to know that if my SD Card 16GB has partition into 2 primary drive - FAT32, EXT3; and my android system is running on FAT32 partition, can I run the Link2SD to put all apps into EXT3 partition?
I try it and it shows the manual of the mounting partition. However, it shows the error message of mounting /dev/block/vold/179:2 on /data/sdext2 failed. I would like to use it even it is in SD version of Android so that I can minimize the usage of internal ROM. I use the traditional App2SD and the memory is gradually reduced when I install new apps.
Thanks
Wilson Fung said:
Hello Guys
I would like to know that if my SD Card 16GB has partition into 2 primary drive - FAT32, EXT3; and my android system is running on FAT32 partition, can I run the Link2SD to put all apps into EXT3 partition?
I try it and it shows the manual of the mounting partition. However, it shows the error message of mounting /dev/block/vold/179:2 on /data/sdext2 failed. I would like to use it even it is in SD version of Android so that I can minimize the usage of internal ROM. I use the traditional App2SD and the memory is gradually reduced when I install new apps.
Thanks
Click to expand...
Click to collapse
SD Android uses no ROM. The applications are stored on what is read by the system as 'internal storage' but is actually a data.img file which is normally 1gb, therefore you already have 1gb of your SD card dedicated to storage of apps. I don't know if you still would like A2SD despite this, but I thought this would probably influence your decision.
Nigeldg said:
SD Android uses no ROM. The applications are stored on what is read by the system as 'internal storage' but is actually a data.img file which is normally 1gb, therefore you already have 1gb of your SD card dedicated to storage of apps. I don't know if you still would like A2SD despite this, but I thought this would probably influence your decision.
Click to expand...
Click to collapse
Thanks for your reply. When downloading apps, Android will treat it storage at the internal storage, that is, the memory reduces very fast. Using App2SD will help to show higher memory storage, which is similar to NAndroid. However, the memory is still lowered as it seems to move the apps only to outside, keeping data internally. Therefore, it can download up to 60-70 apps, but it is impossible to store like 200apps. Link2SD could solve it, but I cannot link to EXT3 after using it. Any suggestion on it?
Good day
I have European device with limited memory
I want to know if there's a way to use the sd card storage to increase the total size of the device memory
Thanks
Most roms support app2sd or data2sd,, backup your SD card, enter cwm, advanced, partition SD card. This creates a partition on your Sd card formatted EXT format, which the system will use as internal memory without you doing anything.
I dunno if you can force your already installed rom to move stuff to the SD, or if you have to reflash to activate it.
When its active, you should make sure all your apps are set to use phone memory not SD card, if you click "move to SD card" it takes them out of the ext partition and puts them to the fat partition, thus defeating the object of the ext.
Hello,
for quite some time now I have been trying to move data from my internal memory to the sd card, as my internal memory is always filled to the brim.
As apps like Link2SD have either not worked or randomly stopped working, I want to take the same approach as I would on a Linux machine; Just making symbolic links.
The problem I am having is that I seemingly cannot make a symbolic link to my FAT32 formatted sd card. When formating the sd card to something else, like EXT4, the system doesn't mount it automatically anymore.
There is of course also the option to change the mountpoint of the sd card to /data/, but that of course doesn't work on a running system.
Long story short: How would I go about changing the mountpoints? On normal Linux systems you could edit the "fstab" file, but on my android system there is multiple fstab files which all have different rules inside; None of which fit the actual mountoptions that are seen in "mount".
I would like to keep to the official rom, as I have gotten quite used to it over the years and don't want to wipe my data to install something else.
Of course I have full access to all partitions. (at least as far as I know). I know my way around systems like debian and ubuntu, but have fairly little idea about android.
Well it is not possible to do that i think, FAT32 with ext4? No not possible, also a SD card can't be formatted to ext4 easily (Only works on some models of SD cards), but you can do a few things here:
1. Get a EMMC upgrade from local repair shops with all the data backed up from the old EMMC
2. Try other apps to link SD cards
3. Get a better/compatible SD card
4. You can actually use the built-in tool to do that, take a look: https://mobiletrans.wondershare.com/xiaomi/move-apps-to-sd-card-xiaomi.html
Hope this helps! If it doesn't, get back to us with some more details.
Happy Hacking!